AKABILLY

Currently my car idles a little low, not enough to stall, but low @ 450 and @ 350-400 with the Head Lights on. Other than that it runs fine.

So I'm trying to adjust my TPS with the Test LED's. I have done it before no problem. EXCEPT now I get nothing when I hook the lights up to the GREEN plug thingy. No matter how far I turn the TPS screw I can't get either LED to light. WHAT THE HELL DOES THAT MEAN?

Did I blow a fuse? Is there anything I should check?
Has this happened to anyone else?

Help!

Thanks

HeffBoost

The car needs to be fully warm before testing/adjustment first off. Why wouldn't you try to raise the idle with the screw on top of the manifold?

Aaron Cake

iTrader: (1)

Don't waste your time with the stupid LEDs. Use an ohmmeter to adjust the TPS for 1K resistance after the car has completely warmed up.

As for your low idle, fix that before you mess with the TPS. Probably due to a vacuum leak, fouled plug, etc. Don't mess with any of the idle adjustments to compensate for another problem.

saltlakebay

I agree with Aaron. Borrow a friends multimeter. Takes less time and is easy as pie:

http://fc3s-pro.com/TECH/HOWTO/TPS/tps.html

AKABILLY

Alright, thanks for the help.

AKABILLY

Well I went and bought a quality digital volt meter ($45). However even with the voltmeter I get no readings on the GREEN plug. And yes I warmed the car up to opertating temperature. Like I mentioned in my post above even the LEDS do not light no mater how far I turn the TPS screw and same with the Volt Meter it has no reading at all. As I mentioned before I have set the TPS before with the LED's and it worked fine.

Is there a fuse that the GREEN diagnostic plug relys on? What exactly does it connect to?

As for the vacuum leak I suspect its in my brake booster, I notice that when I depress my brake my RPMS drop like 100 rpm and stay down as long as my brake is depressed and then return when released. Where exactly would I look for a Vacuum leak on the brake booster?

Roy James

You know, i read somewhere that a guy on here burnt a resistor in his ECU using "test lights" to set the TPS. I currently use LEDs and that seems to be the best way for me, yeah, i can set the TPS to 1K ohm but its never right for me. When you use the LEDs you see what the ECU sees and relays back to you. After i used the LEDs to set my TPS i went back and checked the ohms at the TPS and it was about 750 OHMS. Food for thought. I hope you didnt burn your ECU out.

AKABILLY

Uh, so how do I test the ECU for that, is it something I can visually inspect?...Do I buy a new one or do I fix it?

AKABILLY

BUMP

AKABILLY

BUMP

Aaron Cake

iTrader: (1)

Um, you don't use the voltmeter on the green plug.

Shut the car off, disconnect the TPS and then connect your OHMMETER to the top and right (assuming plug is held with the "point" up). If you don't get a reading, try top and left. My mind is fuzzy right now. Now, adjust your TPS for a reading of 1K. (1000 Ohms). Make sure the car is nice and HOT during this procedure.

AKABILLY

Aaron Cake ok, thanks. But I'm still concerned with the fact that my LEDs did not light up at all. Is that a potential ECU problem? If so, how do I check the ECU? If it is fried where can I get another one?

AKABILLY

BUMP

Roy James

I dont think that the burnt resistors will matter on the ECU itself. But im not sure, i think they are just for that green test connector. What wattage leds did you use? Thats the method i use and im kinda scared that ill burn mine out.. hhmm.. Maybe ill use two voltmeteres instead of lights, who knows. Good luck. Run a search and see if you can find that thread.

hugues

the TPS checking procedure using the led lights relies on signal from ECU to the relief solenoid valve and the switching solenoid valve

See rx-7 86-88 technical page

under emissions->secondary air injection

You should check the signal at the ecu. If ok, then check wiring to the solenoids and to the tps check plug. If not ok, get another ecu (ebay ? or someone on forum in parts section).

You could also just check the voltage the ECU gets from the TPS. Shoud be about 1.0 V at idle with a fully warmed engine. See posts by HAILERS on how to do it if you don't know.

The drop in rpm when you press the brakes could also be due do a bad BAC valve or bad ecu to bac connection.
See same web page under idle control.


Hugues -

HAILERS

There is one thing that I don't think has been mentioned here. AT the green check connector. There are two sockets side by side and one all by itself. Does that one that sits by itself have 12v on it when the key is to ON?????

HAILERS

Oh! Your are worried about whether the ECU transistors are fried! Well, after warming the car up, pull the Blue (relief solenoid) plug on and off. Do you feel it click??? Should because it should be getting a ground from the ECU at idle. Has 12v all the time but the ground is put on it by the ECU at idle if the tps is set right

The lights on the green check connector come and go as the grounds for the switching and relief solenoids come and go. Same grounds as stated in a earlier post.

AKABILLY

Hailers

What is the location of this Blue (relief solenoid)? Is it attached to the ECU?

Thanks

HAILERS

On the drivers side of the engine, the left side, there should be several solenoids. One should have a Blue connector on it. That is the Relief solenoid. You should also have a Grey connector on a solenoid. That's the switching solenoid, and a Brown connector going to the Auxillary ports solenoid(non-turbo) and a couple more colored plugs on solenoids.


Anyway, IF the car is fully warmed up, you should be able to gently shove this plug on and off and feel the solenoid click. If it does that, then the transistors are not fried in the ECU.

Another way is to pull that large hose off the bottom of the ACV with a fully hot engine. There should be but a whisp of air coming out of it. Now reach over and pull the Blue connector completly off. When that is done, a tom of air will come out the bottom of the ACV. If that happens as described, then the transistors are not fried in the ECU.

I wish you had a meter to put on the green check connector. One lead on the socket that sits by itself and the other on a good ground should give you 12v at that socket. That would give us an idea if the problem lies with no voltage at that socket or no ground being put on the other two sockets at the proper time.

AKABILLY

Ok, just so that I'm clear these procedures are done with the car at normal operating temperature and not running, but with the key in the "ON" position. Correct?

hugues

key ON or engine running.

engine running at idle is fine.

Check if you have 12 V at top spot of TPS check green connector (that's from main relay).

If you don't have that as HAILERS said, you're wasting your time

Hugues -